Systems have been proposed that manage equipment errors via a network (for example, refer to Japanese Patent Publication Laid-open No. 2002-44750 (pages 1 to 7, FIG. 1 to FIG. 5)). For example, with a system of Japanese Patent Publication Laid-open No. 2002-44750 (pages 1 to 7, FIG. 1 to FIG. 5), information for equipment errors is sent from equipment to an observation center via a network. The errors of the equipment are then analyzed at the observation center. Equipment errors are then managed via the network.